With almost 60% of the population vaccinated with the complete schedule and close to reaching 70% with at least one dose, according to the latest update from the Ministry of Health, the rate of vaccination continues and, with it, allows to delve into the possible side effects derived from the inoculation of the different vaccines.
Although they may vary depending on the vaccine, among the best known – and common – are pain at the injection site, fatigue or a feeling of tiredness, headache or fever. But these preparations against covid-19 can also generate different skin reactions, including herpes zoster or ‘shingles’, through the reactivation of the chickenpox virus.
This is demonstrated by a study carried out from 405 patients with skin reactions after inoculation with Pfizer, AstraZeneca and Moderna, which reveals that in 13.8% of the cases analyzed this herpes zoster was manifested.
Cristina Galván, a dermatologist at the University Hospital of Móstoles and principal investigator of the aforementioned study – recently published in the British Journal of Dermatology-, explain why. The doctor assures, in statements to 20minutos, that when chickenpox passes, “the virus stays in the body” dormant and, before the alteration of the immunity derived from the vaccination, “what is called a herpes zoster” is produced, that is to say, the denominated “shingles”.
More often with the Pfizer vaccine
In this sense, the vaccine, which prepares the body to defend itself against SARS-CoV-2 that causes covid-19, it can reactivate the chickenpox virus in some cases. And, although this reaction has been seen with all vaccines, according to The dermatologist points out about the study carried out, it has been registered more frequently in patients in whom the Pfizer vaccine had been administered.
Furthermore, in terms of the aforementioned research, among the cases of varicella zoster virus reactivations studied, “in none has herpes recurred after the second dose”, Galván assures. Which implies that, in light of the results of the report, in case of having this type of reaction after the first dose, the patient could complete his vaccination regimen.
Hives or ‘covid arm’, other reactions
The study, which was conducted between February 16 and May 15, 2021, maintains that skin reactions after vaccination against SARS-CoV-2 are “heterogeneous”.
Given this heterogeneity, this same research also describes other skin reactions such as the so-called ‘covid arm’ or urticaria. In the case of the first, a reaction of redness, swelling and pain occurs around the area of the arm where this vaccine has been pricked. According to Galván, this is a reaction that can appear in all vaccines, but occurs more frequently after Moderna and among women.
In this sense, the ‘covid arm’ may or may not recur after the second dose and is treated with local cold or, where appropriate, with elemental treatments. “What is known is that it is never serious or prevents the administration of second doses“, emphasizes the dermatologist.
Likewise, urticaria is also one of the effects on the skin that COVID vaccines can produce, especially that of AstraZeneca, and it is usually treated with antihistamines, explains the doctor. This type of reaction does not usually force altering the vaccination regimen: “It is only considered dangerous to administer the second dose when it comes to hives that appear immediately, right after injecting“, explains Galván.
Skins with hyaluronic acid
To the above skin reactions is added another that affects people who, for aesthetic reasons, have some type of filler in the skin, such as hyaluronic acid. “It is known that it also happened with other vaccines,” underlines the dermatologist at the University Hospital of Móstoles, and with those against covid it also occurs, “but it is very, very rare,” he adds. However, “in all the cases described they have been cured soon with the treatments that are advised”, concludes the dermatologist.
This study analyzed the 21 days after injecting the vaccines, but according to the doctor, the time of appearance of the reactions “is very variable and depends on the type they are”. In addition, the majority of those analyzed were “mild to moderate and self-limited”, although some of greater severity were also recorded, according to the text. In figures, of the 405 cases studied, eighty reactions (that is, 21%) were classified as serious or very serious and 81% required treatment.